Quartz oscillator for controlling transmitter valves and oscillation generators



1,839,208 MITTER VALVES 1932. H. EBERHARD QUARTZ OSCILLATOR FORCONTROLLING TRANS AND OSCILLATION GENERATORS Filed March 22, 1928 (57 2wepforr WM m ' low power.

Patented Jan. 5, 1932 UNITED STATES PATEN -OFFIC HEINRICH EBERHARD, orBERLIN-LICHTERFELDE, GERMANY QUARTZ OSCILLATOR FOR CONTROLLINGTRANSMITTER VALVES AND OSCILLATION GENERATORS y 1 Application filedMarch 22,

My invention relates to V piezoelectrical crystals such as quartz whichmay be used by means of effects of resonance as oscillators forcontrolling transmitter valves and oscillation generators or asresonators for controlling the frequency of any kind of oscillations.

It is a well known fact that valve transmitters for wireless telegraphymay be controlled by quartz crystals. It has not, however, been possiblehitherto with the aid of the quartz directly to control considerableamounts of energy, as are'transmitted by high power valves, thereforeusing piezoelectrical crystals was limited to comparatively Bydeveloping and technically improving the circuits means have alread beenformed for directly controlling wit the quartz larger valves too of theorder of 100 watt and above. In doing so, it has, however, beendiscovered that the quartz crystal is subjected to much heating alreadyby the considerable amplitudes and, perhaps, also by dielectric losses.This heating is very disadvantageous to the permanent working of suchquartz controlled transmitters. According to my invention such permanentoperations may be carried through also with direct controlling ofpowerful valves by oscillating quartz crystals if special coolingsurfaces are used for draining off the heat arising, more particularly,however, also if the quartz is made mechanically large enough in orderto allow of such cooling surfaces being efiectively used. In thisrespect great advantages are derived from the fact that the naturalelectrical oscillation, which is important for the working of thecrystal as an oscillator and as a resonator, depends essentially onlyupon the dimension in the direction of the electric axis while thedirections of the quartz crystal lying at right angles thereto arewithout any considerable influence upon the frequency of wave length. By

merely increasing the size of the quartz 'crys tal it is thereforepossible to use effective cooling surfaces in order to allow of thecontrolled power being magnified. Appropriately the cooling surfaces arearranged as electrodes for the quartz crystal.

My invention may be best understood with 1928, Serial No.

263,701, andi n Germany March is, 1927.

reference to the accompanying the drawings:

Figure 1 shows a piezoelectrical oscillator device arranged in aglass-vessel, the quartz being seen from such aside that the electricalaxis of the quartz is lying in the plane of the drawings.

Figure 2 shows the same device from a direction perpendicularto that ofFigure 1, the electrical axis of the quartz being arrangeperpendicularly to the plane of the drawings. In Figure 2 the upper partof the glass vessel is broken off.

In the drawings a piezoelectrical crystal 3 is arranged between themetal plates 1 and 2 which lie in parallel planes plate 1 beingsupported by standards 7 sealed on the press of the valve. This quartzis shaped in such a way that it forms a thin plate axis of the quartzlying in the direction perpendicular to the planes of the twometalplates and therefore in the direction of the shortest dimension ofthe crystal. In Figure 2 by means of dotted lines the rectangular shapeof the quartz is to be seen. The metal plates 2 and 3 are large enoughto provide a good cooling effect for the crystal if it gets hotwhenoscillating. The electrodes 4 and 5 are connected to the metal-plates 2and 3 in such a way that they are able to bring up the electricaloscillation to the sides of the crystal. 5 are performed as springs asthe figures illustrate, the metal-plates 2 and 3 operating in the deviceat the same time as electrodes as shown in'the drawings. The wholedevice is arranged in a glass vessel 6 which is preferably highlyevacuated in order to avoid uncontrollable discharges between theelectrodes.

However, it may be useful after evacuating the vessel to fill it with akind of gases such as helium or a combination of helium and neon. Thus,if the great amplitudes of the oscillation arise this will be indicatedby lighting effects between the electrodes and the quartz caused byionizations of said gases.

I claim:

A piezo-electric oscillator for high energy two rectangular of exactlyeven thickness; the electrical For this purpose the electrodes 4 and Idrawings. In t":

slgnature.

HEINRICH EBERHAR-D.

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